Capsulating machine



Aug. 22, 1944. l

v R. P. scHERER cAPsJLATING MACHINE Filed June 24, 1940 `es sheets-sheet 1 Y Maf/@7M ATTORNEY 5.

Aug. 22, 194,4.

R. P. SCHERER cAPsuLATINGMAcHI'NE Filed June 24, `1940 Y e sheets-sheet 2 ihlll. 'In Il'.

I o"0 20 34 l' 43mg: 4-0 34- Min; if i I MH'IIHI'I'H.

1N VENTOR.

@M1/rm ATTORNEYS.

Aug. 22, 1944.

R. P. scHERER CAPSULATING MACHINE -Filed June 24, 1940 6 sheets-sheet s y .NN NQ Q m5 D@ QN y INVENTOR. Y F0552?? ATTORNEYS.

Aug. 22, 1944. R. P. scHERER CAPSULATING MACHINE INVENTOR. @GEEFT F? SDH/EPEE y ATTOPNJ S,

Aug. 22, 1944. R, P SCHERER n. 2,356,436

CAPSULATINGvv MACHINE Filed June 24, 1940 6 Sheets-Sheet 6 UWM MME@

A TTORNEYS.

Patented Aug. 22, 1944 i 'mesne asslgnnientajto Gelatin Prod Detroit, Mich# 'a c?? poration, Michizan Application June .24, 194i), Serial 10 claims- This inventionre'lates to theuidfllledsealed capsules and particularly to improvements in machines for` manufacturing -capsules yof -this character.' In my copending application, Serial No'. 336,- 110, tiled May 20, 1940,` I have described vingen- V eral a capsulating machine composed of a num.

ber of lunits Aall operatively .associated together in Y acompact apparatus,1and particularlyhavede'- scribed and claimed the unit-for mounting and operating the die rolls used to form the capsules.

The present invention relates to a part/or unit of the machine and particularly to that part of the apparatus which vmeasures and delivers under pressure the ller material which is capsulated.

An important object of this inventionisto provide improvements in the apparatus for measuring and deliveringflller material and .especially the i'lller material in accurately metered quanti-V ties tothe feeder which injectstthel material into possible vla' Yvirtue o'f .the 119ml 'mamans referred t0 bvf t0 raise the pump uhitvandf the feeder head therewith Vand expose the'ejection"partsV 'of the curatedosages' This;isfa'ccoinplishedby the profeeder headf'for inspection cleaning. vNovel bprat'irie'ineahs 'is provided 'for fconunuing the operation V,of the parts'eve'n when'jthe pump unit israised relat' etothemac e. i v' vnt feature of the invention is' the provisiodof a novelliquid or oil seal in the pumping devices which prevent .theescape and waste of capsuleller `material and insures a'cfvision .of inovel means ivhichfdelivers to "the chambero'f vthe pumping device a supply of oil which forms a' seal betweenY the cliarriiiier walls 'and l th 'side .of the piston reci roatine therein.

l deuveredaiidmaintained'atapressure slightly improvements in the mechanism for rpumping the capsules asthey are formed.v -It-is possible by virtue of this novel mechanism tore'gulatethe' quantity from `very small, quantities toyery large Y quantities and' to makelthe variations in quantity while the mechanismis l'urictiiming. Animportant feature of the mechanism is the positive cut o of filler material after an .accurate measurement of -ller Vmaterial hasbeen `determined for one capsule.

-Another important object of thisrinvention -is to provide a novel valve control memberyvhichis v kso shaped and constructed that it. alone controls the admission and discharge of two or more sets of pumping devices. .Another objectis'tocprovfide novel operating mechanismV for driving the pumping devices, including Y means for. varying the pump stroke. of the devices l with0ut; StPpIv1g the operation. Y

Anotherimportant Afeature ofa machineconstructed in accordance with 'thisinvention is Ithe Y' ability to inspect and clean parts, andf e`specially the feeder headfwithout interrupting theoperation ofthe parts.

novel means for 4cutting off the delivery `of ,cap-

fteract anytenidency, of 'the cape- Yaniageserldmerito- 'il .appear from the arid 15C- "for Figi f6 iS.

cnn :une the ,seinem anni sule filler material tokthe feeder'lheadwhile the pump mechanism is` Astill operating,-The .machine, as previously described, is, .compos ed of a number of units'operatively assembledtogether.

The feeder head isvfloatingly attached tothe unitVV containing the pumping mechanlsmrand ii;is i'v5l.H

"but below the die rolls 20g- 20.

' site one-another.

f motor 50 constitutes thefdrivingI force.

connected to a vertical column shaft 52 by beltthan momentarily interrupting the operation of themachine.

Referring to Figs. l and'2, the machine comprises a base unit or column supporting a pair of rotating casting drums |2-|2,one on either side thereof. Supported on each side of the front part of the base unitl l0 is a unit I4 carrying a'A gear mechanism generally indicated at 64 which connects shaft 62 with a shaft 66. This last shaft extends upwardly into the pump unit 22 and carries on its upper end a bevel gear 68 driving a bevel gear 10 fixed to crank shaft 12.

This last shaft drives the `pumping devices for delivering metered quantities of filler material to series of oil rollers I6. These rollers project forwardly and upwardly from the peripheries of the drums. Superimposing the front section'of the base unit is a unit I8 which carries a pairfof'for-v wardly projecting die rolls 20-20 andV contains operating mechanism therein for Ydriving the same. On top of this unitis the pumpunit `22 to which this invention primarily relates. EX- tending from the pump unit are a plurality of :tubes 24 which lead to a feeder head 26 having vits wedge-shaped bottom edge entering between the two die rolls 20-20.

. Above the pump unit is a vat 28 for containing capsule'ller-content material.

rial in the vat flows into thepump chambers of Y 1 the pump unit as will be later described. Above The matethe rear section of ,the base unit is a vat 30 for containing the capsule shell forming material.

This material ows into a spreader box 32 having -an inclinedfront wall and an adjustable gate above each drum which Vallows a stream Vof this g -material to flow upon the peripheryI of eachy vThe drums rotate .infrthe direction ofY the ar- .row in Fig, l. The shell material spread on the periphery ofthe drums forms an integral sheetor band by the time it reaches the oil rollers I6. f It is then taken off of the drums and conducted ;byv the rollers VI6 to a position in line with Each -band ofcapsule forming material indicated at 34 is next roll 38 superimposing one; ofrthedie rolls 20. From this point the two bands 34-34 converge and come together as they pass between the die rolls. The feeder head 26 rides upon the -bands and discharges filler-material between'the.

bands as the cavities in the die rolls come oppo.-

rolls, stripper rolls 40-40 dislodge the filled capsules from the bands. The balance of the Abands continue downwardly between mangle rolls 42-42'to a suitable receptacle. Y

.The moving parts in the different units are Yconnecting shafts and gears. In the embodiment of the invention illustrated herein,vv an electric It is ing and bevel gear assembly shown in Fig. 1.

lThis shaft is connected by gearing to ay second vertical column shaft54.- `A horizontal columnplungers'.

the feeder head; VThrough a cam element 14 it also drives a valve control member which regulates the admission and discharge of the filler material into and from the pumping devices.

Referring to Figs. 3 to 7, the crank shaft '|2 carries a square shaped bearing 16 fitting within a yokel 18 supported for reciprocating movement by'the oppositely projecting arms 80-80 When operated, the yoke. is adapted to reciprocate two frames 84 and 86 each carrying a set of pump pistons or Asbest shown in Fig. 5, the frames 84Y and 86 are arranged to telescope upon one another, that is to sayfframe. 86 which is narrower in Ywidth than frame..84 is arranged to slide -within the latter.V Frame 84 comprises two `side arms 88-88 longitudinally channeled on their. inner sides-to receive and guide the two sidev arms V90--90 -of the smallerframe member` 86. The latter is bridged by two cross members 92 and94 formed integrally with theside arms. A cross member 96 iforming, a separate element is-connected to the side arms 88-88 of the largerframe. The side arms 90--90 of the small- 'er frame are, slottedlongitudinally as at 98 in Fig. 3 to allowcross member ySli to pass there- Vthrough. TheY slot isr oversize the width of the o 1 The yoke 18 when itis reciprocated bythe crank passed through guide 36 and thence over a feedl After passing between the die e strikes first cross member 94 and then upon reversal the cross member 9S.

VThe two frames 84 and 86 are adjustably secured together for joint reciprocation. `This is accomplished by the provision Vof a threaded member |00 having itsl reduced innerl end secured to cross member 92 -as shown-in Fig 3.

Member |00 is threaded toa surrounding sleeve v |02 havingV a shoulder |04 abutting against the inside of the end of frame 84. It is obvious that through the threaded connection the two frames are coupled together for joint reciprocation. Boththe sleeve |02 and member |00 project out through one of the side walls of the pump unit.

' driven from a single source of power by rinter- The projecting end section of the sleeve |02 is knurledas shown in Fig. 5 to facilitate manual turning. It is obvious from the assembly of the parts relating to this feature that upon rotatf able adjustmentA of the sleeve.|02 the threaded Vmember |00 will move longitudinally in one diadjustment will vary the stroke of the pumpshaft 60 which in turn drives the two mangle l vdrums 42-42 referred to above.v

Shaft54 extends upwardly into theV bottom end of the die roll unitY |,8 and there through interconnecting gearing described in my copending application it drives a. vertical shaft 62. ThisY or wedge a split section |08 of member |00.

ing devices which force capsule content mate- ,rial under pressure intothe capsules being formed. To lock this assembly in any adjusted position, a smaller threaded member |06 extends axially through the larger member 00 and is provided with a tapered inner extremityA which is adaptedwhen advanced to radially expand A knob ||0 aids the operator in tightening the adjustment the desired amount.

As previously mentioned, two sets of pumping devices are operated within this pump unit.

these pumping devices.

. series of semi-circular recesses.

ve pistons, there being ten The sets alternate in function so that while one is discharging metered quantitiesof iilterrmaterial the other is being lled preparatory to ejectionunder pressure. The frames 84 and 86 each carry a set of pump -pistons which operate in Each piston set is secured to the outer end of its respectiveframe. A piston of the set carried by the frame84 is shown at ||2 in Fig. 3. A piston of theset carried by frame 86 is shown at ||4 in Fig. 3

and also in Fig. 5.- The upper surface of the outer ends of each frame is provided with a the piston supporting frames, and arebored out' to receive sleeves Vforming chambers |24 and |26 in which the pistons reciprocate. The 'blocks |20 and |22 are supported in any suitable way l such as by keying and bolting down on to body -of pump unit. The blocks are positioned on vop posite sides of central metal block |28; and bolts `|30 secure the blocks together against Vdisplace-y ment. The blocks areso assembled `that the chambers of the twojsets of pumping devices are in line with one another on opposite sides of the central block |28.

Between each oppositely disposed pair of chambers |24 and |26, the central block is drilledV to form passages for conducting filler material to and away from the pump chambers. As shown in Fig. 3, a passage |32 extends from the top middle portion of the central block and opens out through the side of the block into each pump chambers. Similarly a second vpassage |34 vextends from the top of the block downwardly and thence out through the side of the block to open into each pump chamber. Passage |32 is referred to as the pump admission passage or conduit; passage |34 as the discharge passage or conduit.

Movable along the top of the central block |28 is a slide valve member |36. The valve member is shaped in a novelmanner to control all the .passages leading to and from the chambers The outer 'end body cuts off the passage of lluid. In the position illustratedY in Fig. 3, the admission passage |32 leading to rchamber |26 is opened through the valve member to the top side thereof while the ycorresponding admission passage to chamber |24 is cut off. Similarly, the discharge passagel |34 leading from chamber y|24 is openwhile the corresponding discharge passage` for. chamber |26 is out off. 'I'he control exercised by the slide valve over thepassages illustrated in Fig. 3 is also true of the' passages vleading to the vremaining chambers inthe two sets of Dumping devices. The position of the valve member in Fig. 3 is at one Aend of its movement. When shifted to the opposite end of its movement the open and closed conditions of thepassages. are reversed.

As previously mentioned. the slide valve is operated in timed relation to the functioning of ythe pump pistons. Atl the completion of the-for'- Ward and rearward strokes of thel pistons the slide valve moves from one of its control positions tov the other. This is accomplished by ar novel cam drive receiving impetus from the crank which drivesy the pistons. Referring to( Fig. 4, Ythe crank shaft carries on its rear end a pinion |38 meshing with a pinion |40. .This is xed to the cam member 14 previously described which Y is provided with a-cam slot |42 in the periphery p thereof. Projecting into the cam slot is a stud member 14 rotates it will slide rthe valve member back and forth. The cam slotis so formed and related tothe position of the crank thatthe slide valve moves from one position to the other while the pistons on the frames are resting after ogfrboth sets of,v pumping devices in such a way that theadmission passages of'one set and the discharge passages of another set open and close together, while in "reverse order the admission passages of the second set and the Vdischarge passages of the first set areopened and closed together. The slide valve is operated in timed relationto the strokes of the pistons so that'the admission passages of one set of pumping devices are open when the pistons are retracting `fluid and the-passages |35 either Aalign with discharge passages |34 and form extensions thereof or are displaced to one side so that lthe valve Vcompletion g of Vtheir forward and. rearward strokes. Y Y Y Above the slide valve |36 is a metal block |48. This block is secured by bolts |50 which pass by on opposite sides of the slide valve and enter the central block |28 as shown in Fig. 3. The bolts also pass through spacer elements 52-I52 on opposite sides of the slide /valve which carry the 'weight of the structure thereabove and alsoV form a guide for holding the/slide valve to straight line movement. Blocl:` |48 is cored out toform a longitudinal passage |54 justA over the slide valve as Fig. k4 indicates. Vertical openings |56Y are provided at spaced intervals establishing communication between the passage |54 and the Ytqp of the block |48.` Superimposing the block is-a ilat plate |58 also secured to the vassembly by the bolts |50. This plate is provided with passages |60 aligning with the opening |56. y

As previously described, the Vat 28 for con/tain- `ing the capsule ller content material is attached `passages |60 and thenceinto the openings |56 of the block |48. lIt is obviousihat in operation the filler content material will flow downwardly from the vat andbe'delivered to'the pump chambers. The retracting movements of the pump pistons will. in addition to rtherforce of gravity, create a suction drawing the filler material from the .tank into the pump chambers.

VThe block |48 is provided with passages |62 opening out on the top side of lthe slide valve |36v in Aalignment with the discharge passages is slidable.

Dec.' 5, 1939.

` left and right.

|34. The flat plate |58 is provided with passages |64 opening into communication with passages !62. Passages |64 turn and open out Vthrough the side of the plate member. The plurality of tubes 24 extend from the opposite sides of the plate |58 and the end of ea'ch tube is fitted to the outside opening of each passage |64. As

ends a flat plate |80 which forms part of the feeder head. is plate is fixed to fthev top of the converging side wall fportion of the'feeder head 26 in any suitable way. The feeder tubes 24 leading from the pump unit extend perpendicularly downwardly toward the plate |80 'and fare fitted thereinto in any suitable way. The

feeder head is provided with passages extending as'continuations of the tubes 24 and opening out through the apex -of the head. The construction of th e feederV head and its'relationship to the die rolls is described and` claimed in my copendi'ng application, Serial No, 301,666, filed The 'arms |14 connect the feeder head to the pump unit 22. vThe form of connection, however, is ysuch thatV the feeder head is permitted a limited movement in all directions except longitudinally. The slidable fit of the pins |18 in the sleeves |16 allows the head to rise and fall. The swinging movement of the arms |14 onv the hinge pins |12 allows the feeder head to shift This freedom of movement allows the feederhead to adjust itself to irregularities in the operation of the die rolls and form an "air tight seal between the surfaces of the die 'rolls and the concave sides Aof the feeder head.' The connection provided'by the arms |14 between the pump Aunity and the feeder head enables a novel operation to be performed, namely,

`to bodily lift the feeder head from between the die rolls at the time Athe pump unit is raised relative to the machine. This allows the operator to inspect the feeder head, and to change or clean the feeder headlwith convenience. Moreover, as will be described below, the feeder 'head and pump unit can beraised without disturbing the operation of all the other functions.

The pump unit 22 is mounted upon the upper ends oftwo supporting rods |82|82 (Figs. 3 and 4) which extend vertically downward into therdie roll unit I8. Each of the rods |82 is racked with teeth |84. In engagement with the rack |84 are the pinionsv |86 fixed to a horizontal shaft |88 which projects out through one side of the unit I8. On the projecting end of the shaftis a handle |80. Normally the pump unit 22 rests upon the top of: the die roll unit I8. When the handle |90 is swung in one direction, the pinions |86 on the shaft |88 is rotatedand causes the rods |82 which they engage to rise and lift the pump unit. After the pump unit has been raised a certain distance` the-sleeves |16 on the arms |14 connected to the feeder head abut the heads'of the pins |18 and cause the feeder `head to rise with the pump unit. Dotted lines in Fig. 4 represent two positions of the baume, lsu. The lowerY position is that assumed by the handle when the pump units 22 The pins |18 carry on their lower rests upon the Ydie roll unit I8. The upper dotted representation of the handle corresponds tothe raised position of the pump unit in Fig. 4. The unit cany be raised'to a height considerably above that illustrated in Fig. 4. f

As previously mentioned it is possible to'raise and lower the pump unit andthe feeder head without stoppingthe operation of the moving parts of the machine. This is accomplishedA by slidably keying the gear change mechanism genera-ily indicated at |54 to the drive shaft 66 of the pump unit. The shaft 66v is provided with flat portions |92. A gear wheel |94 of the speed change mechanism is shaped to fit the flattened section of shaft 66` and is keyed thereto. Y As aresult, shaft 66 may be slidingly drawn through the` gear-wheel |94 ans the pump unit isV raised. Nevertheless, so long as the shaft extends through the gear wheel a driving relationshipis maintainedv between the two elements. Gear wheell94 is driven fromgear wheel |96 fixed'to the top of the drive shaft 62 in the die roll unit. When the pump unit is raised sufficiently it is possible to reach under and change the gear mechanism in anyY suitable way such as by substituting a diferentgear wheel for` the gear ,wheel |96.

relationship between the pump unit 22 and the Such a change will alter the drive die roll unit` |8. Raising the pump unit 22 vtherefore not only lifts the feeder head from tinue to be ejected from the discharge openings along the apex of the feeder had; This is accomplished ina novel manner by the yprovision of controll `valves :and associated structure which are capable o f Vby-passing the ller material back' to the inlet side of the pumping devices. .Re-

ferring to Figs. l and 3, the block |48 contains two drilled openings' each extending from the front of the machine rearwardly through a setl of delivery passages |62. In each drilled opening is a rotary valve member 200. Each valve member is provided with a series of diametric passages 202 which in the position shown in Fig. 3 align themselves with the discharge passages |62.

Each valve member is provided with a series of notches 204. Opposite each notch is a short horizontal passage 206 which opens into the larger vertical passages |56 extending between the vat 28 and the passages |32 leading to the inlets of the pumping devices. The notches 204 on each valve member 200 are of such a length that the valve can be utrned to open communication between the transverse passages 206 and the discharge passages |62. At the same time the diametrically extending passages V202 are turned out of linewith the passages |62 cutting bers.

surfaces of the machine, particularly along the cylinder walls in which the pistons H2 and H4 operate. intended ydosage for the capsules but also in many cases foul the moving parts of the machine causing-them to deteriorate at a faster rate, More,-

'over, vif the content material is inflammable, leakage of Vthis character increases the lire hazard. A novel provision is made forl preventing leakage of filler material from rthe pumping devices. Thisis accomplished by providingan oil seal along the cylinder walls around the pistons which is" maintained at a pressure slightly greater than the pressure exerted by the pistons on the filler content material to'discharge this material from the pumping devices. As a' result the oil seal counteracts any, tendency of the content material to leak Yout of the pressure chambers past the pistons. The oil vused is of innocuous character so that'if any trace flowsinto the 'pressure chambers Yit will not effect the dosage capsulate'd.

To provide the oil seal and maintain it at the desired pressure, the blocks |`and i22 are each provided with a passage 2i!) y.which extend transversely to the chambers |24 and' 126 and open out into the bores in which the sleeves forming the chambers are fitted. Ports 2| 2 open c'ommunication between the passages `2li! and `the chambers |24 andl26. The passages and ports are so arranged that the oil is delivered to the annular groove of the cylinder wall at alocation never uncovered by the face of. the piston. Oil is delivered-tothe passages 2I0 by tubes 2id communicating with a source of oil under pressure which is not shown. Fittings 2i6 on the ends f the delivery tubes connect the tubes Withthe passage 2li) in a leak-proof manner.

What I claim is:

l. Ina capsulating machine, a metering device for discharging regulated amounts of capsule ller content material between sheets of capsule shell forming material comprising, incombination, a pair of pumping devices each including a.

pump chamber and a pump plunger therein, a

support for each plunger, means for connecting said supports together, means acting upon said connection for jointly reciprocating said plungers and means for adjusting said connection to vary the distance between said supports and thus vary the stroke of the plungers in their respective chambers.

2. In a machine for capsulating fluid"fllled sealed capsules, means for feeding ller content material to each capsule shell as it is formed.

yoke-shaped members together for joint reciprof This leakage will not only alter thev ports one for admitting' ller material and the 5 cation, said .last means being adjustable to vary the -spacing of the yoke-'shaped members and therebyvary the length of stroke of the plungers in .their respectivechambers. Y

3. In a machine -for capsulating Iluid filled sealed capsules, pumping mechanism for delivering variable v.quantities of ller content. mate` rial to the capsules being formed includinga vrevolving crank, a pair o'f yoke-formed members straddling the ycrank at an intermediate portion of their lengths, each otsaid members carrying..

at least one pump plunger on its outer extremity,

a pump. chamber receiving each pump plunger 1 having means for admitting filler material and means: for .discharging the -same therefrom, means i connecting -said `yoke-formed members together, said crank actin-g when revolved to reciprocatev the yoke-formed members and the plungers carried thereby, and means for adjustving vthe spacing l of said yokeformed members relative Vto one another Ito Yvary the length of the stroke of the plungers.,

In armachine f or capsulating fluid filled l sealed capsules, Vpumping mechanism for delivering variable quantities of capsule filler material to the capsules being formed comprisinga pair' of pumping devices each including a pump chamber and a plungerv reciprocating therein, a revolving crank, a pair of yoke frames straddling said crank, each yoke frame havingan outer transverse section on having engagement with V one ofthe plungers and an inner transverse section on the other side of the crank with which 5. In a machine for capsmating uuid-oued' sealed capsules, pumpingmechanism for delivering variable quantities of capsule filler material n to the capsules being formed comprising a pair 'of pumping devices mounted inline and eachincluding a pump chamber and a. plunger recipro cable therein, frames. straddling said crank and .mounted for reciprocatingmovement in a path .perpendicular to the axis of revolution of said crank, each yoke frame composed of spaced parallel s'idesections extending -past said Vcrank and transverse sections on either side of said crank' connecting the side sections together, said crank in its adapted to alternately strike one of verse sections of each yoke frame and cause the sametobemoved in its path of movement, means connecting eachyoke frame to aplunger for joint movement together, a threaded member vextendrevolution said transingin the line of movementV of said yoke frames, and connecting the two lframes 'togetherfor joint movement, said member adapted on threaded ad! justment to varyV the extent vof separation of one yoke :frame with respect to onef another and thereby vary the stroke of .the .p1ungers.

6. Ina capsulating machine, a pair of pumping devices, yeach device including a plurality' or in eachcchamber, i plungers of eachV Y pumping chambers, a plunger means connecting the several one side f' of said crank n .the crank engages inv its.V revolution and parallel side sections connecting a revolving crank, a pair of yoke device together as a set for unitary operation,

plunger operating mechanism including means coupling said two sets of plungers together for joint operation to advance the plungers of one set on their `exhaust strokes while withdrawing the plungers of the other s et on their intake strokes, g and an adjustment acting onvsaid coupling means j to vary the strokes of the several plungers.

7. In a machine of the character described, a v

pair 'of oppositely disposed pumping devices,each

Vdevicehaving a battery of. aligned pump chambers,a piston reciprocablewithin each'chamber, plunger-operating mechanism including' means connecting the several plungers in each device together for joint operation and means connecting the several `plungers'ofone device to the sev. eral plungers of the other 'device for unitary setting the limit of the intake stroke position oi' each plunger withoutv varying the limit of the exhaust stroke position. i

9;,In a machine of the character described, in combination, a pair of oppositely disposed pumping. deviceseach device including abattery of aligned pump chambers, each chamber provided with an intake and an exhaust. a plunger reciprocable within each chamber) a. pair of telescoping yoke frames, supported for reciprocating telescop- Y ing movement, means coupling the several plungers of one pump device with one yoke frame to reciprocate therewith, means coupling the several plungers of the other pump device with the otherA yoke frame to reciprocate therewith, an. e

. abutment carried by each yoke frame, pump drivoperation to project theseveralplungers of one deviceon their exhaust strokes while withdrawing the several plungers of the other device on their intake strokes, said operating'mechanism provided with an adjustment operable to adjust the relative position o! the several plungers of the ing means having a part interposed between said abutments operable to engage said abutments and reciprocate the yoke frames, and means operable p to adjust the spacing of said abutments relative to each otherto'vary the stroke of the pump plungers. A Y

10. In a vmachine of the character described, in combination, 'a pair of oppositely disposed pumping devices, keach device lincluding a batteryof aligned'pump' chambers, a block interposed between said two devices and having an exhaust passageway andv an intake passageway leading from each pump chamber through theblock and opening out on the top `face of the block, an apertured valve plate slidable'across the top faceV of the several plungers in onedevice to the several j.

plungers in the other device for operation to pro- J'ect the plungers of one'device on theirexhaust strokes while withdrawing the plungers ofthe other device on their intake strokes,:saidfmech anism provided with anadjustment operable to vary the length of the strokes-cfg thelrseveralY plungers as a unit and to the same extent by rethe block and'controlling the flow of fluid throughy the passageways from the several pump chambers,

drivingmeans connected with ,the several plungers of the two devices operable to reciprocate said plungers, and a driving'conneotion between said driving means and said valve plate to reciprocate', thevalve plate in synchronism with the recipro- A cation of 'the pump plungers.

ROBERT l?. SCHERER. 

